If you read what myself and bilkid have noted just above we have already tried resetting the FIREFOX sandbox levels without success and I am not using Sandboxie at all. the problem remains. With firefox. I have also tried nightly 61, beta 60 versions w/o any change.

As you may not be aware, Sandboxie and firefox's sandbox are two different products from different unrelated companies. As are the sandboxes in Chrome and Yandex and Comodo's browser variants (which also have working sound).

CAVE CANEM RADIX LECTI ET SEMPER PARATUS"We want a few mad people now. See where the sane ones have landed us!" George Bernard Shaw (1856-1950)